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MUSIC: "Our World" theme

Straight ahead on "Our World," bankers pledge billions to help top world cities go green ... The Hubble telescope discovers more dark matter ... and the potential of telemedicine:

MARS: "So if one has a dermatologist on-call for half a day, that half-time post could actually service all of the difficult cases of dermatology in our region."

Those stories, emerging diseases and the need for early warning, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

Sixteen cities around the world will share $5 billion in private funds to help them go green with environmental upgrades under a plan unveiled this week by former U.S. President Bill Clinton.

As we hear from VOA's Adam Phillips in New York, the plan would support installation of more efficient heating, cooling and lighting systems, and architectural enhancements that would save enough energy to cover their costs.

PHILLIPS: It was a sparkling spring day Wednesday when Clinton announced the Energy Efficiency Building Retrofit Program at the C-40 Large Cities Climate Summit of big city mayors, business leaders and environmental experts:

CLINTON: "We now have the technology to reduce energy consumption in buildings by 25 to 50 percent. If all buildings were as efficient as they could be, we'd be saving an enormous amount of energy and significantly reducing carbon emissions. Also, we'd save a ton of money for people who pay utility bills. Today we announce a program to perform these improvements on a massive scale in 16 major cities around the world."

PHILLIPS: The cities include Bangkok, Karachi, Seoul and Climate Summit host New York, where Mayor Michael Bloomberg has already produced an ambitious proposal to reduce the city's greenhouse gas emissions. It calls for a 30 percent reduction in carbon emissions by 2030. New York City official Jeffrey Kay, who helped develop the plan, says it focuses on three main areas.

KAY: "One, cleaning up our energy, getting more clean power, better energy supplies, solar power [and] distributed generation. The second is reducing the amount of emissions from our buildings, making them more efficient. And third, reducing the amount of greenhouse gas emissions and air pollutants from our transportation system.

Every city has its own combination of challenges to consider and solutions to share, says Cynthia Rosenzweig, a scientist at NASA's Goddard Institute for Space Studies in New York. She spoke at the launch last week of the Urban Climate Change Research Network, where scores of urban environmental scientists from around the world had gathered to share both research results and practical experience.

ROSENZWEIG: "For example, we have a researcher from London telling us about the Thames barrier for sea level rise. We have a researcher from Berlin, who is a green roof specialist. We have a researcher from Japan who is telling us about ventilation corridors through the streets of Tokyo."

PHILLIPS: Rosenzweig adds that, in addition to efforts to reduce greenhouse gas emission in cities, scientists at the conference also discussed ways to adapt to the climatic extremes that global warming has already caused, and future effects they say are now inevitable.

ROSENZWEIG: "For example, helping our urban population to deal with heat waves. It's helping folks on the coasts to make weather storm walls around coastal areas that we need to protect or to even possibly draw back, or to have wetlands so that we can buffer the sea level rise storms. Other adaptations are managing our reservoirs for our water systems better."

PHILLIPS: Conservation can be a hard sell to emerging middle classes in boom economies such as China's, where large new cars are fashionable, and where large new homes are also a symbol of progress. But New York mayor Michael Bloomberg says the question should not only be whether you develop…

BLOOMBERT: "It's how you develop. It's not just having a job. It's whether or not you can stay healthy and enjoy the fruits of your labor. And more and more you're reading about the Chinese government understanding this and trying to do something about it. You know, if you make a little step every day, after a period of time, you look back and are shocked at how far you came."

PHILLIPS: Indeed, even today's greatest and most powerful optimists such as President Clinton urge caution alongside their hope that the mayors' initiatives will help cities save the planet.

CLINTON: "And the thing I like about working with the mayors is, they are in the 'doing' business. Look, this is like everything else. Some of these programs will work better than others. Some cities will be more successful than others. The exhilarating thing to me is we're back in the solutions business."

PHILLIPS: The mayors themselves also seemed energized by the spirit and the substance of the conference. "Agog with ideas" was how London Mayor Ken Livingstone put it. Many mayors say that while the world's national governments have been slow to address global climate change with the urgency they say it deserves, they ended the C40 Large Cities Climate Summit with a communiqué to the G-8 Summit to be held next month in Germany. For Our World, I'm Adam Phillips in New York.

Infectious disease like Ebola or AIDS can move from animals to humans, and the authors of a new study of the phenomenon say the world needs an early-warning system to protect against future emerging diseases.

That's the conclusion of a team of University of California (Los Angeles) researchers who analyzed the origins of major infectious diseases in a paper published this week.

Author Nathan Wolfe, who has observed the process up-close in West Africa, says the interface where humans and animals come into close contact can provide an alarmingly efficient way for disease to jump from animal to human.

WOLFE: "A lot of things are going to be jumping at that interface, whether it be viruses that infect hunters when they're out in the forest, perhaps by mosquitoes that previously might have fed on some wild animals, whether it be a cut or a scratch while butchering. And if you're, you know, somebody who's a hunter or if you're butchering wild game in these areas, you're using a machete and, you know, if it's a daily part of your life, eventually you'll cut yourself."

Diseases can leap from all sorts of animals to humans. Influenza, for example, originates in birds. But Wolfe says the analysis by him and his co-authors — including famed biogeographer Jared Diamond — indicates that the greatest threat comes from mammals and, in particular, animals closest to humans.

WOLFE: "We've demonstrated, I think for the first time, that animals that are more closely related to humans are disproportionately responsible for the introduction of diseases which end up becoming major human diseases. So in particular, non-human primates including monkeys and apes."

Because of the risk, Wolfe and his colleagues call for a systematic global program to monitor animal pathogens that might threaten humans in the future. They stress the need to act before diseases appear in humans, comparing the threat of emerging infectious disease in a way to heart disease. Today, doctors monitor blood pressure and cholesterol and try to stop the problem before it happens. Decades ago you just waited for a heart attack.

WOLFE: "Y'know, that would seem ridiculous to somebody now. And I think in 100 years the notion that we just wait for something like a pandemic like HIV to spread throughout the world and become completely established where it's going to be nearly impossible — I mean, phenominally hard and it's going to take years and years and years to control that — that at least we should be spending a percentage of our effort attempting to do preventative disease forecasting work. And I think the future will be crystal clear on that point."

University of California researcher Nathan Wolfe. His paper, on the importance of monitoring animal-to-human disease transmission, appears this week in the journal Nature.

The most deadly new disease of recent years is AIDS, which was first described in 1981. Despite intensive effort, an AIDS vaccine has proved elusive, and as we hear from VOA's Rosanne Skirble, a vaccine could be useful even if it is not 100 percent effect in preventing the disease.

SKIRBLE: In this week's New England Journal of Medicine, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, discusses prospects for an AIDS vaccine. He says while the ultimate goal is prevention — much like that for polio, smallpox and measles — combating the AIDS virus requires a different strategy.

FAUCI: "The non-classical approach would be to accept the possibility that you can get some advantage, that you have a vaccine that might not effectively block initial infection, but could block the level of virus, the first blast of virus that you get, and then level of persistent virus such that you could have multiple effects."

SKIRBLE: Fauci notes that the number of infected people might not go down at first. He says the vaccine's initial benefit would be to block secondary transmissions of the virus. And Fauci says a number of promising vaccines are in the pipeline.

FAUCI: "There is one candidate that is a collaboration with the company Merck, in which we take a relatively benign type of a common virus called an adenovirus — and you call that a vector — and you insert into that the different components of HIV, and you vaccinate individuals with that particular vectored virus."

SKIRBLE: The National Institutes of Health is leading a similar research effort. Both NIH and Merck are testing large numbers of people in the United States and in other countries for safety and for protective response. Fauci says these interim vaccines would work in tandem with the two dozen or so antiviral therapies currently available.

FAUCI: "… because if you block the progression, but the person still has a significant degree of virus replication going on, you may need to have drugs come in and supplement or complement the disease-modifying vaccine."

SKIRBLE: Anthony Fauci says the success of the disease-modifying vaccines could be a major advance in the development of an AIDS vaccine. An estimated 14,000 new AIDS cases occur every day. I'm Rosanne Skirble.

Time again for our Website of the Week, when we showcase interesting and innovative online destinations.

Last Sunday was Mother's Day here in the United States, and that got us thinking about how important it is that mothers stay healthy. And that got us thinking about the health of women in general. And that brought us to our Website of the Week.

Wanda Jones is the Deputy U.S. Assistant Secretary for Women's Health, who oversees WomensHealth.gov, a U.S. government website that tries to bring together any and all issues affecting the health of women, including some that you might not immediately think of as a health issue.

The site also includes the latest health news, tools such as a body mass index calculator, tips on talking with doctors and nurses, and for younger women there's a companion site — girlshealth.gov — with lots of help for getting through those difficult years from 10 to 16.

While the site is mainly in English, there is a significant amount of Spanish language content, and even some in Chinese.

The web is full of sites that provide health information, but Wanda Jones points out that unlike many of the others, WomensHealth.gov is paid for by U.S. taxpayers and doesn't take advertising.

JONES: "We have nothing to sell but health. We may cite studies that have studied one or more commercial products, but in the direct information that is flagged as U.S. government-source information, that information can be trusted to be based on the most credible science. This is a public trust issue."

It's all been carefully vetted by experts. Check it out at WomensHealth.gov, or get the link from our site, voanews.com/ourworld.

When a patient can't get to a doctor, sometimes technology can help bridge the gap. Telemedicine allows health care specialists to look at x-rays or examine patients who might be thousands of kilometers away. Reporter Christine Buttorff visited the annual meeting of the American Telemedicine Association in Nashville this week and had a look at the technology, but she found that many countries are still facing technical and financial challenges in using even basic technology to deliver health care to hard to reach places.

BUTTORFF: Health care experts in Africa say the continent faces the double burden of too much disease and too few doctors.

Maurice Mars works on telehealth issues at the Nelson R. Mandela School of Medicine at the University of Kwazulu-Natal in South Africa. He says in his region, there are fewer than 10 doctors for every 100,000 people.

MARS: "In our region for example, which is about 100,000 square kilometers with 10 million people, we have in fact three pediatric surgeons who are in one town. We have five dermatologists who are in one town. So all of the other larger hospitals in our region have nothing."

BUTTORFF: Telemedicine is in its infancy in Africa, with only a few successful programs that can treat people in remote settings. But Dr. Mars says it has promise for alleviating the physician shortage.

MARS: "The concept of setting up a virtual hospital so if one has a dermatologist on-call for half a day, I believe based on the numbers that I've got, that half time post could actually service all of the difficult cases of dermatology in the 65 hospitals in our region."

BUTTORFF: Other poor countries are using telemedicine more effectively. Dr. Asif Zefir works at the Holy Family Hospital in Rawalpindi and directs the Telemedicine Association of Pakistan. He recalls the chaos that hampered relief efforts after the 2005 earthquake in Kashmir.

ZEFIR: "And shifting them into the main hospitals, there was a lack of coordination there and we would not know how many patients would land in our hospital, and all those emergencies would just come in ambulances and then in half an hour you would have, what, 50, 100 coming in. So that was the situation, that was a problem there."

BUTTORFF: But within a week after the quake, Zefir says mobile telemedicine units — made up of a laptop computer, a digital camera and a satellite phone — were helping track the patients from the disaster site. The patients in local hospitals nearest the epicenter could also be treated and monitored remotely.

ZEFIR: "So this helped us enormously in a way that we could coordinate these activities. We could know almost what the day to day needs were in that time, because there was virtually no communication established between the main hospital and the remote disaster sites. Because, you see, this earthquake, virtually the entire terrestrial [communication] network was damaged."

Beyond its applications in disasters, telemedicine is connecting U.S. specialists with physicians and clinics in developing countries. Boston University medical student Kavitha Reddy says a six-year-old Harvard Medical School project she's working on uses straightforward technology.

REDDY: "It basically connects through email, which is what we call 'store-and-forward technology,' that's essentially saying email that is not in real time. connecting patients in remote Cambodia, in these two village,s with specialists in the Harvard system who are volunteering to provide consultation on these cases."

BUTTORFF: Another project — connecting psychologists at the University of Kansas with a school for children with developmental disorders in Peru — started out with an expensive software and video system donated by the University. The doctors found that it actually worked better to use Skype, an application that allows people to make phone or video calls over the internet.

At the Nashville telemedicine meeting, the technology on display was anything but simple or affordable. Troy Dionne holds a small camera, about the size of his hand, to the arm of his coworker, Kent Greenough.

BUTTORFF: The camera is connected to a video screen, which magnifies the small scratch into a bloody gash. It's used for remote diagnostics and treatment, but Dionne of MedVision Telehealth Solutions says it's not cheap.

DIONNE: "This system will range, with high definition, with the scope, about $38,000."

BUTTORFF: For developing countries, that kind of expenditure is not an option. In fact, basic internet service in many countries is barely affordable, as South Africa's Maurice Mars points out.

MARS: "People seem to take internet and email access as almost in fact given. One needs to be reminded that in many developing countries, the internet service provider is in the capital, and where we want the service is in the deep outlying areas which means a long distance phone call."

BUTTORFF: Regardless of the technical and funding obstacles, the real challenge is ultimately a human one: finding enough qualified people to participate at both ends of the technology. For Our World, I'm Christine Buttorff in Nashville.

Finally today, scientists peering through the Hubble Space Telescope have discovered a ghostly ring they believe to be "dark matter," a substance that does not shine or reflect light, but is thought to be the most common element in the universe. VOA's Stephanie Ho has more on the story.

HO: How do you take a picture of something that you cannot see? That was one of the main problems for Myungkook James Jee, an associate research scientist at Johns Hopkins University.

JEE: "We can not see a wind, but we can see what it blows."

HO: Jee co-authored a paper that will appear in next month's Astrophysical Journal. It recounts his observations of a ring of "dark matter," a mysterious substance that is invisible but very much prevalent. Scientists do not know what dark matter is, but say it makes up about six-sevenths of the total amount of matter in the universe.

Jee believed the ring of dark matter he saw through the Hubble Space Telescope was formed long ago during a collision between two massive galaxy clusters.

His fellow investigator, Richard White, is with the Space Telescope Science Institute, which makes Hubble's findings accessible to the public. White says although dark matter cannot be seen, it exerts a gravitational pull. He said Einstein's theory of relativity, in which gravity can bend light or cause things to change their direction, applies in the case of the ring of dark matter.

WHITE: "When light passes by massive objects, it changes direction. So the effect is when you have objects that are far away, and you have some massive object between us and the very distant galaxies, the galaxy shapes get changed by the presence of the mass, which exists there in the cluster."

HO: He gave an example that compared dark matter to clear water. He said seeing objects through the water slightly distorts their true shape.

WHITE: "In the same way that if you were looking at pebbles at the bottom of this pond, that had a wave on it, you could watch the wave and see the pebbles changing shape."

HO: The photo of the discovery displayed on the Hubble Telescope's webpage is beautiful. However, Richard Massey, a scientist at the California Institute of Technology, said the findings are being met with "substantial skepticism among the astronomical community."

MASSEY: "It's really exciting if it's right. But to be sort of convinced of the ring [of dark matter], astronomers would really want to see some independent observations, verifying it."

HO: At the same time, he congratulated the science team on its work to examine dark matter. He called dark matter the most common stuff in the universe, and said it is embarrassing that humans know "almost nothing about it." Stephanie Ho, VOA News, Washington.

MUSIC: "Our World" theme

That's our show for this week. We're always interested in your comments. Email us at ourworld@voanews.com. Or use the postal address:

Our World Voice of America Washington, DC 20237 USA.

Rob Sivak edited the program. Eva Nenicka is the technical director. And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.